JP7336797B1 - cutter - Google Patents

Abstract

To provide a cutter that cuts the boundary between a base metal surface and an old coating film and at the same time grinds and completely removes the old coating film shavings that remain attached to the exposed base metal surface.
A cutter main body (2) is formed in a flat disk shape in which a flat one-sided bottom surface (4) and a flat surface (5) are provided in a parallel positional relationship. An inclined surface portion 6 is provided on the entire peripheral edge of the flat surface 5 , and the edge of the entire peripheral edge is sharpened and provided with a grinding tip 7 . A mounting shaft 3 is provided at the center of the plane 5 of the cutter body 2 . The bottom surface 4 is provided with a portion 9 which is coated with a hard abrasive coating.
[Selection drawing] Fig. 1

Description

The present invention is a cutter that is attached to the rotating shaft of a high-speed rotary drive tool in order to completely remove the old paint film adhered to the surface of a metal structure and expose the base metal surface where the old paint film does not remain. Regarding.

Radio towers, bridges, etc. are constructed from metal members such as steel plates and steel connectors. We are trying to prevent deterioration due to rusting etc. A coating film applied to the surface of a metal structure dries and hardens with the passage of time, and cracks and fissures may occur. Water enters through cracks and fissures and reaches the metal surface of the structure, causing rust and shortening the life of the structure. In order to prolong the life of metal structures, it is necessary to remove the old coating film and repaint it with a new coating film.
Conventionally, the grinding and peeling work of the old paint film adhered to the iron surface is performed by attaching the cutter disclosed in Patent Documents 1 to 8 to the rotating shaft of a high-speed rotating tool such as a grinder, and removing the bottom surface of the disk or wheel. The disk or wheel is rotated in the circumferential direction while being pressed against the surface of the old coating film, and the surface of the old coating film is scraped off with a grinding chip or the like provided on the bottom surface of the disk or wheel. It has been proposed to scrape off the old coating with a grinding tip provided on the surface.
In the conventional grinding and peeling operation of the old paint film, only the surface portion of the old paint film is scraped off, and the old paint film that was not completely scraped off remains adhered to the iron surface. If it were attempted to completely remove the old coating with a grinding tip, it would take time, and at the same time as the old coating was peeled off, the grinding tip would scratch the iron surface, resulting in the deterioration of the structure. Therefore, conventionally, the surface of the old coating is ground and the old coating that could not be scraped off with a grinding tip remains on the iron surface without scratching the iron surface, and the new coating is overlaid on this remaining old coating. was to be painted. After several decades have passed since the first coating on the metal structure, the iron surface of the metal structure is covered with old coating layers of different coating times due to repeated coating repair work. A coating film layer having a thickness corresponding to the number of times of repair work was formed. The layer thickness of the old coating layer may range from several centimeters to more than 5 cm, depending on the number of years the metal structure has been constructed. In repeated repairs in which a new coating layer is applied to the surface of the old coating layer, the thick old coating layer hardens after many years of drying, and a substantially vertical groove wall extends from the surface of the old coating layer to the underlying iron surface. There are many cracks that crack with
For the above reasons, the grinding and peeling of the old paint film using a cup-type rotary grindstone (see, for example, Patent Documents 1 to 8) or a rotary grinding tool having a grinding tip on the peripheral surface (see, for example, Patent Document 9) However, there is a problem that the old paint film cannot be completely peeled off from the iron surface, but only the surface of the old paint film layer is scraped.
Further, there has been proposed a device in which small substrates are attached to front and back surfaces of a thin main substrate (see, for example, Patent Document 10). If the rotating blade disclosed in Patent Document 10 is used for cutting and peeling off the old coating layer, it is not preferable because the peripheral edge of the small substrate forms scratches on the underlying steel surface.

Design gazette of registration No. 948281 Design gazette of registration No. 1425143 Design gazette of registration No. 1425533 Design gazette of registration No. 1416758 Design gazette of registration No. 1223034 Patent publication of Japanese Patent No. 5218546 JP 2013-86216 A JP 2016-5851 A Patent publication of Japanese Patent No. 5924139 JP 2016-5851 A

The present invention has been devised in view of the above-mentioned problems of the prior art, and the cutter body is formed in the shape of a flat, thin disk with a horizontal back surface, and the entire peripheral edge of the flat surface has a predetermined inner and outer width. By making the range an outwardly sloping surface and sharpening the edge of the entire circumference, the edge of the main end of the cutter can be easily and accurately inserted into the boundary between the old paint film and the base metal surface, and a predetermined interval is provided around the entire circumference. By cutting the adhesive part between the base metal surface and the old coating film with the grinding tip provided, the old coating layer can be quickly separated from the base metal surface as a lump, and the hard grind provided on the flat bottom surface The granular coating contacts the base metal surface and rotates at high speed, so that the old coating film containing synthetic resin is removed by polishing without forming scratches on the base metal surface, and the base metal surface without the old coating film remains. The object is to provide a cutter that allows exposure.

In order to achieve the above object, the invention according to claim 1 of the present invention provides a disc that cuts and separates the old coating film from the underlying metal surface and at the same time grinds the underlying metal surface to remove the remaining old coating film scraps. A cutter used for a grinder, which is a flat circle with a flat one-sided bottom surface and a flat surface provided in a positional relationship parallel to each other, and a grinding tip provided on the peripheral edge with the tip of the cutting edge positioned on the same circumference. It consists of a plate-shaped cutter body and a mounting shaft to which the rotation drive shaft of the disc grinder is mounted, which is erected in the center of the plane of the cutter body, and which is inclined with the same width in the inward and outward direction over the entire peripheral edge of the plane of the cutter body. A surface portion is provided, and this inclined surface portion is inclined downward from the inside to the outside so that the edge of the entire periphery of the cutter body is formed sharply. A portion coated with a hard abrasive grain coating is provided in a predetermined same width range or/and substantially on a radius of the entire peripheral edge of the bottom surface in the inner and outer directions so that the base metal surface on which the film does not remain can be exposed.

In the present invention, by forming an inclined surface on the entire planar peripheral edge of the cutter body and sharpening the entire peripheral edge toward the outside, the cutter body can be accurately inserted into the boundary portion between the base metal surface and the old coating film, There is an effect that the adhesive portion of the old coating film can be cut off from the base metal surface with the cutting edge of the ground tip, and the old coating film can be peeled off as a lump.
Since the back of the cutter body has a part coated with a hard abrasive grain coating, it has the effect of peeling off the old coating remaining on the base metal surface that cannot be cut with the grinding tip by high-speed rotation in the circumferential direction. be. In addition, there is an effect that the old coating film softened by frictional heat is less likely to adhere to the back surface of the cutter.

It is a front view of a cutter body. (Example 1) It is a top view of a cutter main body. (Example 1) It is a bottom view of a cutter main body. (Example 1) FIG. 3 is a cross-sectional view taken along line AA of FIG. 2; (Example 1) It is a partial notch enlarged cross-sectional explanatory drawing of the peripheral part of a cutter main body. (Example 1) FIG. 4 is a partially cut-away enlarged cross-sectional explanatory view showing an arrangement state of grinding chips on the peripheral portion of the cutter main body; (Example 1) FIG. 4 is an explanatory diagram showing the state of use of the cutter main body; (Example 1) It is explanatory drawing which shows the peeling operation|work of an old coating film. (Example 1) It is a bottom view of a cutter main body. (Example 2) It is a bottom view of a cutter main body. (Example 3) It is a bottom view of a cutter main body. (Example 4)

By providing an inclined surface with a downward slope of the same width inside and outside on the entire peripheral edge of the plane of the cutter body and making the entire peripheral edge sharp, the peripheral edge of the cutter body is accurately aligned with the boundary between the base metal surface and the old coating film. By cutting the old paint film from the base metal surface, the old paint film can be separated from the base metal surface in a lump and improved peeling workability. In addition, by providing a hard abrasive grain coating on the flat back surface, it is possible to polish the base metal surface at the same time as the old coating is cut by the peripheral edge of the cutter body, and it is possible to expose the base metal surface without the old coating remaining. did.

Example 1 will be described with reference to FIGS. 1 to 6. FIG. As shown in FIGS. 1 to 4, the cutter 1 consists of a cutter body 2 and a mounting shaft 3. As shown in FIGS.
The cutter main body 2 has a bottom surface 4 that is horizontal and one-sided, and a flat surface 5 that includes a circular portion having a diameter smaller than that of the bottom surface 4 and an inclined surface portion 6 that is continuous with the entire peripheral edge of the circular portion. , and the circular portion of the plane 5 are formed in a circular disc shape in plan view and bottom view having a parallel positional relationship.
The inclined surface portion 6 is inclined downward in a range of the same width in the inner and outer directions from the entire peripheral edge of the circular portion to the outer side, and the outer peripheral edge is connected to the bottom surface 4 via a sharp outer peripheral edge. The inclination angle formed by the inclined surface portion 6 and the bottom surface 4 is set according to the diameter of the cutter body 2 from the viewpoint of user's convenience.

Grinding tips 7 are arranged on the periphery of the cutter body 2 at predetermined intervals in the circumferential direction. The tip of the cutting edge of the grinding tip 7 slightly protrudes outward from the peripheral edge of the cutter body 2 . The cutting edges of the grinding tips 7 are positioned on the same circumference around the center of the cutter body 2, and are arranged with the cutting edges directed radially outward. The grinding tip 7 is made of a material having a high hardness, for example, polycrystalline diamond sintered body or polycrystalline cubic boron nitride crystal body. Fixedly mounted in the groove.

A mounting shaft 3 is integrally attached to the center of the cutter body 2 on the plane 5 at an angle of 90 degrees with the plane 5 . The mounting shaft 3 is provided for connecting the rotary drive shaft of the disk grinder 8 . The mounting shaft 3 is formed as a female screw having a spiral groove carved in the inner peripheral wall of a cavity portion whose upper end is open and whose lower end is closed. As long as the mounting shaft 3 can be mounted on the same straight line as the rotating shaft of the disk grinder 8, any connecting means is acceptable. For example, it may be formed so as to be connected to the rotating shaft of the disk grinder 8 by fitting means. The length of the mounting shaft 3 is appropriately set according to the film thickness of the old coating film 10 to be peeled off.

The cutter main body 2 and the mounting shaft 3 are preferably made of metal with a low coefficient of thermal expansion. Specific examples include iron, stainless steel (SUS), high-speed steel (SKH), alloys of iron and aluminum, and alloys of iron and aluminum and cobalt. To prevent the cutter body 2 from generating heat due to dry cutting due to the high-speed rotation of the cutter body 2, causing bending of the cutter body 2 due to the relationship between thermal expansion and heating temperature distribution, and causing vertical shaking, which makes the cutter body 2 unusable. is.

The bottom surface 4 of the cutter body 2 is provided with a portion coated with a hard abrasive coating 9 . The hard grain coating 9 extends in a tapered radial manner from the center of the bottom surface 4 to the periphery with a predetermined uniform width range in the inner and outer directions of the entire periphery of the bottom surface 4 and a predetermined angular separation in the circumferential direction from the center of the bottom surface 4. It is deposited on the area. The hard abrasive grain coating 9 is formed by depositing hard abrasive grains by electrodeposition. As abrasive grains, diamond grains, cubic boron nitride grains, or mixed grains of diamond grains and hard oxide grains are suitably used. Although the particle size is not critical, it is preferably about 30 to 80 mesh. It should be noted that forming the hard abrasive grain coating 9 from diamond-like carbon (DLC) and coating it on the coating surface using a chemical vapor deposition method (CVD method) or the like is also included in the present invention. Although the layer thickness of the hard abrasive coating 9 is not limited, it is preferably about 0.01 cm. The size of the cutter body 2 and the length of the mounting shaft 3 are appropriately varied according to the thickness of the old coating film 10 to be peeled off. Specifically, the diameter of the cutter body 2 is 12.5 cm, the diameter of the circular portion of the plane 5 is 11.0 cm, the inner and outer width of the inclined surface portion 6 is 1.5 cm, and the diameter of the cutter body 2 at the circular portion of the plane 5 is 1.5 cm. As an example, the thickness is 0.4 cm, the slope of the inclined surface portion 6 is approximately 10 degrees, and the length of the mounting shaft 3 is 4.5 cm. 11 is a grinding chip embedding groove.

Next, a method of using the cutter 1 shown in FIGS. 1 to 6 will be described with reference to FIGS. 7 and 8. FIG. The cutter 1 is attached by screwing the rotation drive shaft of the disk grinder 8 to the attachment shaft 3 . On the inner side of the safety wall 12, the cutter body 2 is surrounded by anti-scattering bristles 13 spaced apart from the entire peripheral edge of the cutter body 2 by a certain distance. One end of the suction hose 14 opens inside the safety wall 12, and the other end is connected to a dust collector (not shown) separately provided outside.
The cutter body 2 is inserted from a crack or a fissure where the underlying metal surface 15 of the old coating 10 is visible, and the peripheral edge of the cutter body 2 is brought into contact with the boundary between the underlying metal surface 15 and the old coating 10.例文帳に追加The disk grinder 8 is driven to rotate the cutter 1. The cutter body 2 cuts the boundary between the base metal surface 15 and the old coating film 10 with the grinding tip 7, and at the same time, the bottom surface 4 of the cutter body 2 rotates on the base metal surface 15 from which the old coating film 10 has been separated. to remove any remaining old coating debris. Since the bottom surface 4 is coated with the hard abrasive grain coating 9, it is difficult for old coating film shavings softened by frictional heat to adhere to the bottom surface 4, thereby improving workability. The hard cutter body 2 advances a distance equal to the radial length of the plane 5 and cuts the connection portion between the base metal surface 15 and the old coating 10 by the radius length of the plane 5 and separates it from the base metal surface 15 . The old coating 10 cut from the base metal surface 15 is a lump. As shown in FIG. 8, a crowbar 21 is inserted between the base metal surface 15 and the old coating film 10, and the peeled old coating film 10 is lifted up by the crowbar 21 and folded with the bonding point to the base metal surface 15 as a fulcrum. Remove. Since the old coating film 10 is hardened, it can be easily folded.
The peripheral edge of the cutter body 2 is brought into contact with the boundary portion between the base metal surface 15 and the old coating film 10 to directly cut the connecting portion, and the bottom surface 4 is brought into rotational sliding contact with the base metal surface 15 from which the old coating film 10 has been cut. Therefore, the peeling/cutting and polishing operations of the old coating film 10 can be performed at the same time to improve the workability, and there is an effect that the slightly remaining old coating film scraps can be completely removed without damaging the underlying metal surface 15.例文帳に追加

Example 2 shown in FIG. 9 will be described. 1 to 6 is that the hard abrasive grain coating 16 is formed on the entire peripheral edge of the bottom surface 17 in the same width range in the inner and outer directions in the circumferential direction, and in the circumferential direction at intervals of 90 degrees from the center of the bottom surface 17. The only difference is that it is formed in a band-like range of the same width extending in the peripheral direction at the position. Since other configurations are the same as those of the first embodiment shown in FIGS. 1 to 6, description thereof is omitted.

Example 3 shown in FIG. 10 will be described. The difference from the first embodiment shown in FIGS. 1 to 6 is that the hard abrasive coating 18 is formed on the entire peripheral edge of the bottom surface 19 over a range of the same width inside and outside. Since other configurations are the same as those of the first embodiment shown in FIGS. 1 to 6, description thereof is omitted.

Example 4 shown in FIG. 11 will be described. The difference from Example 1 shown in FIGS. 1 to 6 is that the hard abrasive grain coating 20 is formed over the bottom surface 21 from the center to the outer periphery in a tapered shuriken shape. Since other configurations are the same as those of the first embodiment shown in FIGS. 1 to 6, description thereof is omitted.

1 Cutter 2 Cutter body 3 Mounting shaft 4, 17, 19, 21 Bottom surface 5 Flat surface 6 Inclined surface portion 7 Grinding tip 8 Disc grinder 9, 16, 18, 20 Hard abrasive coating 10 Old coating 15 Base metal surface

Claims (1)

A cutter used in a disc grinder that cuts and separates an old coating film from a base metal surface and at the same time grinds the base metal surface to remove remaining old coating film scraps,
A flat disc-shaped cutter body having a flat one-sided bottom surface and a flat surface provided in a parallel positional relationship with each other, and having a cutting tip located on the same circumference on the peripheral edge portion and having a grinding tip provided;
a mounting shaft to which the rotary drive shaft of the disk grinder is mounted, which is erected at the center of the plane of the cutter body;
An inclined surface portion having the same width is provided in the inner and outer directions over the entire peripheral edge of the plane of the cutter body, and the inclined surface portion is inclined downward from the inside to the outside so that the entire peripheral edge of the cutter body is formed to be sharp,
A predetermined uniform width range or/and approximate radius in the inner and outer directions of the entire peripheral edge of the bottom surface to prevent old paint film scraps softened by frictional heat from adhering to the bottom surface and to expose the base metal surface where the old paint film does not remain. A cutter characterized by having a portion coated with a hard abrasive coating on the top thereof .

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